1. Field of the Invention
This invention relates to the use of conventional syringes in combination with a newly disclosed frontal attachment having a retractable needle. The invention relates more particularly to a medical device comprising in combination a needle, nose and hub assembly attachable to a conventional syringe preferably having a forwardly facing luer lock connector. The subject device has a needle retraction mechanism that is activated by rotating the syringe barrel relative to the nose of the device to retract the needle from a patient and propel it into the nose and a retraction tube that is part of the hub assembly.
2. Description of Related Art
Conventional syringes comprising a generally cylindrical barrel, a fixed needle projecting forwardly from the barrel, and a plunger slidably disposed inside the barrel through an opening in the rear of the barrel are well known. More recently, syringes have been made with a luer connector on the front of the barrel to which a needle hub is attachable to allow needles of different gauges or sizes to be used with a commonly configured barrel.
Even more recently, in an effort to control the spread of blood-borne pathogens and the incidence of contamination by contact with either exposed needles or bodily fluids, syringes having fixed or changeable needles have been designed to embody various “safety” elements. Such “safety” elements should desirably include a retractable needle, but many products marketed as having “safety” elements include, for example, covers or guards that are manually operated by medical personnel administering an injection to shield or cover the needle tip following removal of the needle from a patient.
Some previously disclosed needle retraction systems without changeable needles are activated either manually or automatically by application of a force upon completion of an injection to force the needle and needle tip back inside a retraction chamber. The only known syringe having a changeable, retractable needle does not have a conventional luer lock connection, and the retraction mechanism is activated by the application of a forwardly directed force to the plunger handle following removal of the needle from a patient, thereby exposing the needle and also exposing the user to the risk of needle-stick injury.
U.S. Pub. No. 2006/0155244 to Popov discloses a venipuncture device that rotates a port unit following needle retraction. The retraction chamber is disposed inside the medical device, is not part of the frontal attachment and remains stable while the port unit is moved rotationally relative to the retraction chamber following needle retraction. The frontal attachment disclosed there cannot be used with a generic luer lock syringe.
Although many advancements in syringe technology have been made in recent years, a frontal attachment device is needed that can be used with a standard syringe having a conventional luer lock connector, that offers the advantages of a changeable needle in combination with the advantages of a retractable needle providing sufficient retraction force to retract the needle while inserted into a patient, and that can be activated by the application of a rotational force to the syringe barrel while stabilizing the nose without applying a forwardly directed force to the plunger or the needle.